Valve control mechanism for air guns



April 14, 1953 J. l.. .JUNKIN VALVE CONTROL MECHANISM FOR AIR GUNS FiledApril 30 1951 rfv/vzw,

I NVENTOR.

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Patented Apr. 14, 1953 UNITED STATES PATENT OFFICE VALVE CONTROLMECHANISM FOR AIR GUNS 9 claims. l

The present invention relates to pneumatic guns and has for its objectto provide a quick firing gun capable of projecting ammunition at highspeed. A further object is to provide a gun within which air iscontinuously maintained under sufcient pressure uninterruptedly toattain such projection velocity, Still another object is to provide avalve control mechanism designed to permit of very rapid ring of thegun.

'These and other objects of the invention together with the manyadvantageous features thereof will be better understood from thefollowing detailed description and by referring to the accompanyingdrawing in which a preferred form of the invention is illustrated.

In the drawing:

Fig. l is a side elevational View of an air gun embodying the invention;

Fig. 2 is a View, on a larger scale, of the rear end of the gun andtaken substantially through the vertical center thereof, and l Fig. 3shows a detail of construction taken substantially on line 3-3 of Fig. 2in the direction of the arrows.

In the form illustrated in the drawings, the device of the inventionincludes a support bracket, or cradle I which is intermediate its endsmounted for oscillating and rotative movement on a pedestal 2 to enablethe person operating the gun to aim the gun in any desired direction.However, since it is the intent and ypurpose of the invention to connethe use thereof to target shooting, the range of movement of the gun islimited by placing adjustable stops 3, 4 on the lower, stationaryportion 2a o the pedestal for engagement by a projection 5 of the upperportion 2b which vis seated for rotation on the pedestal 2e. Oscillationin a vvertical plane is similarly limited by means of suitableadjustable stops 1, 8 of the cradle. In such manner, vit is lseen thatthe range of the gun may be adjusted to suit conditions and to complywith rules governing the use of such devices.

A gun barrel I0 is rigidly vsecured to the cradle and an enlargedcylindrical housing II extends from the rear end of this barrel in axialalinement therewith. This housing is also rigidly secured in position onthe cradle to support therein the pressure control mechanism of the gun,as best shown in Fig. 2. The inner end of the passage I Ie, within whichthe barrel is anchored, is shown recessed to form a seat IIb for themaster valve I3 of the gun and this valve is part of a piston I4. Thisvalve is in order to provide a ytight fit shown tted with an O-ring I2'and the seat IIb is set at 'an .angle of about `60" `relative to theaxis of the gun barrel and valve axis, further to insure such leak-prooijoint and also better to align the valve with its seat. The farmer isseated for limited sliding movement within a cylinder I5 in the mannerand for the y urpose which will now be described.

The cylinder I5 is rigidly secured to a cap I6, which closes the rearend of the housing and is clamped in position thereon in any suitablemanner, as by bolts Il. It is important to note that the cylinder ismuch smaller in diameter than the space within the housing and that, inthis manner, an annular chamber I8 is Vformed about the cylinder. Belowthe housing, within a recess la sunk into the cradle of the gun, isplaced a trigger support 20, through which a passage 2I carries airunder pressure Yfrom a supply hose 22. The latter is in any conventionalmanner connected continuously and uninterruptedly to carry pressurefluid Ito 'the chamber I8, while the gun is in use.

A threaded rod 25 is seated in the piston I4 and rigidly clamped inposition therein by a nut 2B. This rod extends axially through the caplIIS into a recess 23 sunk into the rear end thereof of a diameter toreceive therein a piston `2l. The purpose of this piston is to controlthe operation of the master Valve I3. A plate 24 tightly closes theentrance to this recess. `lt is important to note that the rod 25extends freely into the piston 21 and that a threaded nut 28 at the endof vthe rod engages a shoulder Zie within the piston. A stop collar 30is placed within a groove Ain the inner wall of the recess 2'3 and it isparticularly to be noted that the parts are lso arranged andproportioned that the piston is afforded -very limited `axial movementwithin the recess between this collar and the shoulder 23a.

As above stated, pressure fluid is free to rlow into the lannularchamber I8 to maintain the vmaster valve I3 normally on its seat I2. Atrigger `35 is pivotally secured to the rear end of the support 20 inposition to push a valve 36 away from its seat and so to open a passagefor the pressure fluid through :passages 31, 38 to the bottom vof therecess 23. The uid now entering this recess exerts suiiicient pressureagainst the piston 21 to move the latter rearwardly ,against the stopcollar .30 and, in moving, to push the nut 28 Irearwardly, therebyslightly '.to withdraw the master valve from its seat, against theytension of a spring 39. The latter is merely power- -ful enoughnormally to lmaintain the master valve seated.

The air from the pressure chamber lI8 now rushes through the narrowvalve opening to encounter the resistance of the atmospheric pressureWithin the gun barrel; a resistance which is sucient further to move thevalve I3 away from its seat and so fully to open the valve for the freeflow of the pressure fluid into the barrel. The effect of thisarrangement is momentarily to check the ow of the pressure uid and thento release the uid so suddenly that the instantaneous pressure fluidexpansion and rush through the barrel is accompanied by a very loudreport, not unlike the report of a gun powder exploded gun. It isimportant to note that the rod 25 and nut 28 are free to move within thepiston 21 during this valve opening movement. Y

In the upper surface of the gun barrel is cut an opening I of a size toadmit therethrough a ball 40 which, by the explosive expansion and flowof the pressure fluid is projected through the barrel at an enormousrate of speed to land on the target several rods away from the gun. Aball receptacle or magazine 42 is mounted on the gun barrel, slightly toone side thereof so as to clear the gun sights 43, 44, and means shouldvbe provided for admitting the balls one by one from this magazine tothe barrel. For the sake of simplicity and clearness, this means is inthe drawings shown to consist of a cap 45 of a size normally to closethe opening Il, and a rod 46 extends from this cap to the rear end ofthe housing I I for convenient manual operation to load the gun beforethe trigger is pulled to discharge the ammunition. But, of course, wheresuch cap is used, means must be added to maintain the cap seated on thebarrel.

The proportions of the various parts and of the areas and volumes of thespaces within the gun are of great importance and must be held veryclose limits. It is, for instance, absolutely essential that thediameter of the passage through the gun barrel is a little less than theinner diameter of the cylinder I and the piston I4 seated therein. Alsothat the diameter of the valve I3, at the point where .the O-ring I2contacts the valve seat IIb is greater than the inner diameter of thebarrel. Had the opposite relations existed, the result would have beento cut down the air resistance within the barrel and to increase thepressure resistance behind the piston suiiciently to ease the now ofpressure iluid into the barrel and so to soften the impact of the gunfiring. The tension of the springs 29, 39 is also important and shouldbe merely sucient to overbalance the friction of the pistons I4 and 21within their bearings.

Since, as above explained, the master valve is suddenly projected intofully open position, it is advisable to provide means for arresting thisopening movement and this may be done by placing an annular stop member50 within the cylinder I 5 and to mount a resilient bumper 5I againstthis member for contact by the piston I4 when the valve reaches fullyopen position. The opening through this bumper stop should be largerthan the nut 26 of the valve rod 25 to permit escape of fluid into theinner space 52 during the opening movement of the valve. It is also tobe noted that a passage 53 leads from this space to the recess 23directly behind the stop collar 30 to relieve the pressure behind thepiston 21 While the latter moves to initiate the valve opening movement.A relatively very ne passage 55 leads from the inner chamber 52 throughthe cap I6 to the atmosphereA to assist in equalizat the entrance to thebarrel, a conduit for con- .within the chamber latter being free to move4 ing the pressure within this chamber and the recess 23 each time thegun has been fired.

It should be clear from the foregoing description that I have produced apneumatic gun within which air may continuously be maintained undersuicient pressure to expel projections at high speed and wherein thevalves and valve controlled passages are so proportioned that the areawithin these passages is greater than the inner area of the gun barrel.But While the device described and illustrated is capable of producingthese results, it is not intended thereby to limit the device to theexact arrangements and proportions shown, and modifications thereof maybe embodied within the scope of the claims hereto appended.

I claim:

1. In a pneumatic gun having a barrel and an enlarged cylindricalpressure chamber in axial alinement with said barrel, the wall of thechain- 4ber being recessed to form a co-axial valve seat at the entranceto the barrel, a conduit for continuously admitting pressure iiuid tosaid chamber, a cylinder co-axially mounted within the chamber, a mastervalve slidable within said cylinder, means urging the valve against saidvalve seat, there being a cylindrical recess at the rear end of the gunin axial alinement with the cylinder and master valve, a piston slidablewithin said recess, a co-aXial rod rearwardly projecting from saidmaster valve and freely extending through said piston, a head on the endof said rod contacting the rear surface of the piston, there being apassage from said conduit to the space in front of said piston, acontrol valve normally closing said passage, and a trigger fer unseatingsaid control valve to admit pressure fluid to the space in front of thepiston thereby to force the head of the master valve rod rearwardly Vtoopen the master valve.

2. In a pneumatic gun having a barrel and an enlarged cylindricalpressure chamber in axial alinement with said barrel, the wall of thechamber being recessed to form a co-axial valve seat tinuously admittingpressure uid to said chamber, a cylinder co-axially mounted within thechamber, a master valve slidable within said cylinder, means urging thevalve against said Valve seat, vthere being a cylindrical recess at therear end of the gun in axial alinement with the cylinder and mastervalve, a piston slidable Within said recess, a co-axial rod rearwardlyprojecting from said master valve and freely extending through saidpiston, a head on the end of said rod contacting the rear surface of thepiston, there being a passage from said conduit to the space in front ofsaid piston, a control valve normally closing said passage, and atrigger for ,unseating said control valve to admit pressure fluid to thespace in front of the piston thereby to move the piston rearwardly andin moving to force the head of the master valve rod rearwardly slightlyto open the master valve, the pressure completing the opening movementof the master valve, the rod of the rearwardly through the controlcylinder piston.

' 3. In a pneumatic gun having a barrel and an enlarged cylindricalpressure chamber in axial alinement with said barrel, the wall of thechamber being recessed to form a co-axial valve seat at the entrance tothe barrel, a conduit for continuously admitting pressure fluid to saidchamber, a cylinder `co-axially mounted vwithin the chamber, a mastervalve slidable within said cylinder, means urging the valve against saidvalve seat, there being av cylindrical recess at the rear end of the gunin axial alinement with the cylinder and valve, a piston slidablevwithin said recess, a co-axial rod rearwardly projecting from saidmaster valve and freely lextending through said piston, a headadjustably xed on the end of said rod and contacting the rear surface ofthe piston, there being a passage from said conduit to the space infront of said piston, a control valve normally closing said passage, atrigger for unseating said control valve to admit pressure iiuid to thespace in front of the piston thereby to move the piston rearwardly andin moving to force the head of the master valve rod rearwardly to openthe master valve, and a buffer within the master valve cylinder limitingopening movement of the master valve.

4. In a pneumatic gun having a barrel and an enlarged cylindricalpre'ss'urechamber in axial alinement with said barrel, the wall of thechamber being recessed to form an inclined co-axial valve seat at theentrance to the barrel, a conduit for continuously admitting pressurefluid to said chamber, a cylinder co-axially mounted within the chamber,a master valve slidable within said cylinder, means urging the valveagainst said valve seat, there being a cylindrical recess at the rearend of the gun in axial alinement with the cylinder and valve, a pistonslidable within said recess, a co-axial rod rearwardly projecting fromsaid master valve and freely extending through said piston, a head onthe end of said rod contacting the rear surface of the piston, meansurging the piston against the head of the rod, there being a passagefrom said conduit to the space in front of said piston, a control valvenormally closing said passage, and a trigger for unseating said controlvalve to admit pressure iiuid from said conduit to the space in front ofthe piston thereby to move the piston rearwardly and in moving to forcethe head of the master valve rod rearwardly to open the master valve.

5. In a pneumatic gun having a barrel and an enlarged cylindricalpressure chamber in axial alinement with said barrel. the wall of thechamber being recessed to form a co-axial valve seat at the entrance tothe barrel, a conduit for continuously admitting pressure fluid to saidchamber, a cylinder co-axially mounted within the chamber, a mastervalve slidable within said cylinder, means urging the valve against saidvalve seat, the diameter of the valve at the point of contact with itsseat being greater than the inner diameter of the barrel, there being acylindrical recess at the rear end of the gun in axial alinement withthe cylinder and valve, a piston slidable within said recess, a co-axialrod rearwardly projecting from said master valve and freely extendingthrough said piston, a head on the end of said rod contacting the rearsurface of the piston, there being a passage from said conduit to thespace in front of said piston, a control valve normally closing saidpassage, and a trigger for unseating said control valve to admitpressure uid to the space in front of the piston thereby to move thepiston rearwardly and in moving to force the head of the master valverod rearwardly to open the master valve.

6. In a pneumatic gun having a barrel and an enlarged cylindricalpressure chamber in axial alinement with said barrel, the wall of thecham- 'ber being 'recessed -to form an inclined l:5o-aerial valve seatat the entrance to the barrel, a cons duit for continuously admittingpressure fluid to said chamber, a cylinder co-axialiy mounted within thechamber, a master valve slidable within said cylinder, said valve having-a gasket -fo'r contact vwith said seat, means urging the valve gasketagainst the said valve seat, there being a cylindrical recess at thevrear end of theY gun in axial alinement with the cylinder and valve, apiston slidable within 'said'recesa the space behind the pistoncommunicating with the space within the rnaster valve cylinder, aco-axialrod rearwardly 'projecting from said master valve and freelyextending through said piston, ahead on the end of said rod contactingthe rear surface of the piston, there being a passage from v'saidconduit to the space in front of said piston, a control valve normallyclosing sai-d passage, and a vtrigger vfor unseating said control valvevto admit pressure uid to the space within the cylinder infront of thepiston thereby to move the' piston rearwardly and in moving to force thehead of the master valve rod rearwardly to open the master valve.

'7. In -a pneumatic gun having a barrel and an enlarged cylindricalpressure chamber in axial alinement with said barrel, the wall of thechamber being recessed to form a co-axial valve seat at the entrance tothe barrel, a conduit for continuously admitting pressure iiuid to saidchamber, a cylinder axially mounted within the chamber, a master valveslidable within said cylinder, means urging the valve against the saidvalve seat, there being a cylindrical recess at the rear end of the gunin axial alinement with the cylinder and v-alve, a piston slidablewithin said recess, a co-axial rod rearwardly projecting from saidmaster valve and freely extending through said piston, a head on the endof said rod contacting the rear surface of the piston, there being apassage from said conduit to the space within the cylinder in front ofsaid piston, a control valve normally closing said passage, a triggerfor unseating said control valve to admit pressure fluid to the space infront of the piston thereby to move the piston rearwardly and in movingto force the head of the master valve rod rearwardly to open the mastervalve. and means limiting rearward movement of the piston.

8. In a pneumatic gun including a cradle, a housing rigidly mounted onsaid cradle and having an enlarged cylindrical pressure chamber therein,-a barrel seated in said housing in axial alinement with said chamber,the wall of the chamber being recessed to form a co-axial valve seat atthe entrance to the barrel, a conduit within the cradle for continuouslyadmitting pressure fluid to said chamber, a cylinder axially mountedwithin the chamber, a master valve slidable within said cylinder, meansurging the valve ag-ainst said valve seat, there being a cylindricalrecess at the rear end of the gun in axial alinement with the cylinderand valve, a piston slidable within said recess, a co-axial rod rearwardly projecting from said master valve and freely extending throughsaid piston, a head on the end of said rod normally contacting the rearsurface piston, there being a passage from said conduit to the space infront of said piston, a control valve within the cradle normally closingsaid passage, and a trigger at the rear end of the cradle operable tounseat said control valve to admit pressure fluid to the space in frontof the piston thereby to move the piston rearwardly and Ain moving toforce the head of the master valve rod'rearwardly to open the mastervalve.

9. In a pneumatic gun including a cradle, a housing rigidly mounted onsaid cradle, said housing having an enlarged cylindrical pressurechamber therein, ya barrel seated in said housing in axial alinementwith said chamber, the wall of the chamber being recessed to form a ooaxial valve seat at Ythe entrance to the barrel, a conduit Within thecradle for continuously admitting pressure uid to said chamber, acylinder .co-axially mounted Within the chamber, a master valve slidablewithin said cylinder, means urging the vvalve against said valve seat,there being a cylindrical recess at the rear end of the'gun in axialalinement with the cylinder and valve, a piston slidable within saidrecess, there being a Aspace Within the recess in front of and behindthe pistonl a co-axial rod rearwardly projecting vfrom said master valveand freely extending through said piston, a head on the end of said rodnormally contacting the rear surface ofthe References cited in the me ofthis pai-.entv

UNITED STATES PATENTS Number Name Date 353,430 Reynolds Nov. 30, 18861,299,901 Blair Apr. 8, 1919 1,486,215 Zerbee Mar. l1, 1924 2,525,082Sherman Oct. 10, 1950 2,581,758 Galliano et al Jan. 8, 1952

